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set_clip_rect(3)		Allegro	manual		      set_clip_rect(3)

       set_clip_rect  -	 Sets the clipping rectangle of	a bitmap. Allegro game
       programming library.

       #include	<allegro.h>

       void set_clip_rect(BITMAP *bitmap, int x1, int y1, int x2, int y2);

       Each bitmap has an associated clipping rectangle, which is the area  of
       the  image  that	 it is OK to draw onto.	Nothing	will be	drawn to posi-
       tions outside this space. This function sets the	clipping rectangle for
       the  specified bitmap. Pass the coordinates of the top-left and bottom-
       right corners of	the clipping rectangle in this order; these  are  both
       inclusive,  i.e.	set_clip_rect(bitmap, 16, 16, 32, 32) will allow draw-
       ing to (16, 16) and (32,	32), but not to	(15, 15) and (33, 33).

       Drawing operations will be performed (at	least partially) on the	bitmap
       as  long	 as  the  first	 coordinates of	its clipping rectangle are not
       greater than the	second coordinates and its intersection	with  the  ac-
       tual  image is non-empty. If either condition is	not fulfilled, drawing
       will be turned off for the bitmap, e.g.

	  set_clip_rect(bmp, 0,	0, -1, -1); /* disable drawing on bmp */

       Note that passing "out-of-bitmap" coordinates is	allowed, but they  are
       likely	to   be	  altered   (and   so	the  coordinates  returned  by
       get_clip_rect() will be different).  However,  such  modifications  are
       guaranteed  to  preserve	the external effect of the clipping rectangle,
       that is not to modify the actual	area of	the image that	it  is	OK  to
       draw onto.

       get_clip_rect(3),	  add_clip_rect(3),	    set_clip_state(3),
       get_clip_state(3), ex12bit(3), excamera(3)

Allegro				 version 4.4.3		      set_clip_rect(3)


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